Waterborne Disease Outbreaks and the Multi-barrier Approach to Protecting Drinking Water - Global Drinking Water Management and Conservation - page 27

farming in the region does not have an adverse impact on water quality in the
region. A good integrated management approach should connect all the initiatives
and actions of government agencies as well as local watershed associations
(USEPA 2013 , p. 17). Additionally, the process of integrated management is
continuous, cyclical, and endless; it includes data gathering, assessment, targeting,
implementation, and monitoring (USEPA 2013 , p. 15).

4. Flexible Approach in Watershed Management

fits all. Because each
watershed landscape is shaped by a blend of climate, geology, hydrology, soils, and
vegetation, a targeted approach should be applied to support the watershed man-
agement depending on different regions of the country (USEPA 2013 , p. 20). In
practice, watersheds can change over time, due to (for example) the emergence of
serious diseases or a change in water

The watershed management approach is not one size

flow patterns or due to a change in use
patterns. The objectives and approaches of watershed management should be
adjusted to adapt to changes in water and land use.

5. Application of Ecological Risk Assessment to Watershed Management

The US has strong regulations on point source pollution such as farms with
animals. With the reduced impact of point source pollution (e.g. cattle manure from
a specific farm) on source water quality via multiple legislation or regulations in the
US, the issue of controlling nonpoint source pollution (pollution sources that cannot
be identi ed) is becoming increasingly important both environmentally and eco-

nomically (USEPA 2007 , p. 6). Due to the limitations of being able to find pollution

sources and pathways, nonpoint source pollution problems are not being corrected
by existing regulations (USEPA 2007 , p. 6). For this reason the EPA recommends
an alternative approach, which is the application of Ecological Risk Assessment
(ERA) to watershed management. In practice, the primary principles of watershed
ERA assist the watershed managers to make decisions on such factors as total
maximum daily load of contaminants, resource planning, and land use zoning, and
how to mitigate these expected harmful effects. Since the sources of pollution are
not known, it is a matter of assessing the risks that emerge from a variety of causes.
In the mid-1990s, USEPA

ce of Water
collaborated on testing the application of the ERA approach and recorded all the
details during the experiment by choosing

' s Risk Assessment Forum and the Of

ve watersheds that possessed abundant
ecological resources, available dataset, and multiple stressors (USEPA 2007 , p. 6).
According to the EPA Risk Assessment Forum and the Of

ce of Water, several
researchers found that the application of ERA had been bene cial for watershed

management (USEPA 2007 , p. 6). A complete description of ERA is given in
Chap. 6 , which covers all aspects of risk management.
The key issue in the risk assessment of point source pollution is an adequate
record of agricultural and commercial activity that could impact water courses
within the watershed. Where the agricultural activity involves a large number of
animals (for example cattle or pigs), there have to be clear animal manure man-
agement plans that ensure that none of the manure ends up in the water courses. For